One type of motor vehicle has multiple fuel tanks for holding liquid fuel that is consumed by an engine that propels the vehicle. An example of such a vehicle is a medium or heavy truck that has a right fuel tank on the right side of the truck chassis and a left fuel tank on the left side.
At times during operation of such a vehicle, it may be appropriate to maintain the respective fuel levels in the tanks substantially equal, thereby achieving at least an approximate balance of fuel between the tanks. However at other times during operation of the vehicle, it may be appropriate to reduce the amount of fuel in one tank sufficiently relative to the amount of fuel in the other tank, thereby unbalancing the tanks to some degree.